• International Journal of Automotive Technology
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• v.6 no.5
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• pp.501-506
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• 2005

With the respective collapse characteristics of aluminum and CFRP (Carbon Fiber Reinforced Plastics) tubes in mind, axial collapse tests were performed for aluminum/CFRP compound tubes, which are composed of square or circular shaped aluminum tubes wrapped with CFRP outside. In this study, the collapse modes and the energy absorption characteristics were analyzed for aluminum/CFRP compound tubes which have different fiber orientation angle of CFRP. Fracture modes in the aluminum/CFRP compound tubes were rather stable than those in the CFRP tubes alone, probably due to the ductile nature of the inner aluminum tubes. The absorbed energy per unit volume of the aluminum or the aluminum/CFRP compound tubes was higher than that of CFRP tubes. Meanwhile, the absorbed energy per unit mass, for the light-weight design aspect was higher in the aluminum/CFRP compound tubes than in the aluminum tubes or the CFRP tubes. The energy absorption turned out to be higher in circular tubes than in square tubes. Beside the collapse modes and the energy absorption characteristics were influenced by the orientation angle, and the compound tubes took the most effective energy absorption when the fiber orientation angle of CFRP was 90 degrees.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.215-221
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• 1997

In an effort to screen new selective antitumor agents from the broth of soil microorganism, cytotoxicity oriented screening was performed against tumor cells and 3 compounds (Compound 1, 2 and 3) were isolated from Sreptomyces parvullus ISP 5048 and their chemical structures were determined. Among these compounds, Compound 2 showed the highest cytotoxicity against P388Dl and L1210. While the $IC_{50}$/ values of compound 2 against P388Dl and L1210 were 0.073$\mu$g/ml and 0.07$\mu$g/ml, respectively, and the $IC_{50}$/ value of Compound 3 was 0.17$\mu$g/ml against human lung cancer cells, A549, the cytotoxicity of Compound 2 and 3 against normal cell line, Vero E6 cell was about 4- and 8-fold lower than that of adriamycin. Based on the chemical analysis data, Compound 3 was octacosamicine A, a known antibiotic, which was reported by Dobasih et al. (1988). Taken together the results demonstrated that Compound 2 and Compound 3 has the possibility to be developed as antitumor agent because of its potent cytotoxicity as well as high selectivity against various cancer cell lines.

• Tribology and Lubricants
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• v.13 no.1
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• pp.42-52
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• 1997

This paper deals with wear characteristics of ion-nitrided metal theoretically and experimentally in order to analysis of wear phenomena. Wear tests show that compound layer of ion-nitrided metal reduces wear rate when the applied wear load is mall. However, as th load becomes large, the existence of compound layer tends to increase wear rate. The residual stress at the surface of ion-nitrided metal is measured, and the internal stress distribution is calculated when the normal and tangential forces are applied to the surface of metal. Compressive residual stress is largeest at the compound layer, and decreases as the depth from the surface increases. Calculation shows that the maximum stress exists at a certain depth from the surface when normal and tangential force are applied, and that the larger the wear load is the deeper the location of maximum stress becomes. In the analysis, it is found that under small applied wear load the critical depth, where voids and cracks may be created and propagated, is located at the compound layer, as the adhesive wear, where hardness is an important factor, is created the existence of compound layer reduces the amount of wear. When the load becomes large the critical depth is located below the compound layer, and delamination, which may be explained by surface deformation, crack nucleation and propagation, is created, and the existence of compound layer increases wear rate.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.9-14
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• 2003

When ginsenosides Rbl, Rb2, and Rc were anaerobically incubated with commercial and human intestinal lactic acid bacteria, most commercial lactic acid bacteria did not metabolize these ginsenosides to compound K. However, lactic acid bacteria, B. minimum KK-1, Bifidobacterium cholerium KK-2, and B. cuniculi K-513, isolated from human intestinal microflora transformed these ginsensosides to compound K. When the bacterial mixtures of commercial lactic acid bacteria were incubated with these ginsenosides, these compounds were not transfformed to compound K. However, when Bzfidobacterium KK-1 and KX-2 were miked, these ginsenosides were synergistically transformed to compound K. When water extract of ginseng was incubated with these mixed bifidobacteria, compound K was potently produced. Therefore, it is suggested that, if ginseng with these mixed bifidobacteria is fermented, compound K-enforced ginseng materials could be produced that show cytotoxicity against tumor cell lines.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.673-680
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• 2011

The compound 3-(2-Mercaptopyridine)phthalonitrile has been synthesized and characterized by IR, UV-vis, and X-ray single-crystal determination. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager and polarizable continuum model. Using the TD-DFT and TD-HF methods, electronic absorption spectra of the title compound have been predicted and good agreement with the TD-DFT method and the experimental determination was found. The predicted nonlinear optical properties of the title compound are much greater than those of urea. Besides, molecular electrostatic potential of the title compound were investigated by theoretical calculations. The thermodynamic properties of the compound at different temperatures have been calculated and corresponding relations between the properties and temperature have also been obtained.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.50-56
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• 2011

This paper proposes 3D visualization method of compound knowledge which will be able to identify and search easily compound knowledge objects based the multidimensional relationship. For this, we structurized a compound knowledge with link and node which become the semantic network. and we suggested 3D visualization method using SOM. Also, to arrange compound knowledge from 3D space and to provide the chance of realistic and intuitional information retrieval to the user, we proposed compound knowledge 3D clustering methods using object similarity. Compound knowledge 3D visualization and clustering using SOM will be the optimum method to appear context of compound knowledge and connectivity in space-time.

• YAKHAK HOEJI
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• v.42 no.4
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• pp.395-402
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• 1998

Mori Cortex Radicis, the root bark of mulberry tree, has been used in the treatment of bronchial asthma and other lung diseases in traditional medicine. There was a recent repor t that the water soluble part with molecular weight of above 10,000 has anti-allergic activity. Therefore, we intended to isolate and purify the anti-allergic compound from hot water extract of the Mori Cortex Radicis. Crude extract of Mori Cortex Radicis was prepared by hot-water extraction, and anti-allergic compound was further purified by alcohol precipitation, successive ultrafiltration, anion exchange chromatography and gel filtration chromatography. This compound had homogeneity which was shown by the sharp single peak in HPLC chromatogram (TSK-GEL G400OPW column, RI detector). The molecular weight of the compound was estimated as 23Kda on the basis of calibration curve plotted against protein standards. This compound was identified as complex of sugar, protein and lignin (19.2: 5.9: 72.7), and proteolysis could not decrease the anti-allergic activity but mild delignification decreased the activity remarkably. Therefore, we concluded that the anti-allergic compound of Mori Cortex Radicis was a lignin-carbohydrate complex.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.124-128
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• 1995

The present study was conducted to elucidate nitrite scavenger derived from seeds of Cassia tora L. Methanolic extract of Cassia tora L was refractionated into ethyl ether, chloroform, ethyl acetate and water farction, and nitrite scavenging abilities of these fractions were investigated. Among these fractions, ethyl acetate fraction had the strongest nitrite scavenging ability(97%/2 mg). Therefore, to further investigate nitrite scavenger, ethyl acetate fraction was fractionated by silica gel column chromatography with a chloroform-methanol($10:0{\sim}0:10$) and then compound A and B were isolated. Compound A had a stronger nitrite-scavenging effect than compound B. Therefore the further separation of compound A was carried out by HPLC(32% acetonitrile. 1 ml/min) using ${\mu}Bondapak$C18 column$(3.9{\times}300 mm)$ and finally compound A-1 was obtained from compound A. Compound A-1 had by far nitrite-scavenging ability as compared with that of ascorbic acid. Compound A-1 was identified as $nor-rubrofusarin-6-{\beta}-mono-D-glucoside$ from the profiles of UV, IR and $^1H-NMR$.

• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1829-1834
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• 2001

The choking of dual subsonic streams flowing through a convergent duct in contact has been investigated experimentally and theoretically. The experiment was conducted by using blow-down wind tunnel. The condition, when the dual stream flow chocking (compound choking) occurs at the nozzle exit, was explained by one-dimensional analysis of compound sound wave propagation. The experimental results for the condition of compound choking were compared with the prediction from theoretical analysis, and the schlieren optical method using the spark light source has been used to visualize the flowfield.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.4
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• pp.357-360
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• 2003

Methanol extracts from Paeonia lactiflora showed a strong inhibition against platelet aggregation on platelet activation test. Therefore, the bioactive constituents from Paeonia lactiflora were prepared using chromatography methods and were analyzed by NMR and reference data. Compound 1b was confirmed a same structure with henzoyloxypaeoniflorin, compound 2e was a same structure with paeoniflorin; main product of Paeonia lactiflora. Analytical data of compound 3a were not consistent with any known paeoniflorin soucture, but showed the souctural similarity with it. And also the aggregation inhibition activity of compound 3a showed a strong inhibition($\geq$ 90%) induced by collagen. Therefore it suggested that the structure of compound 3a may be the similar structure of benzoyloxypaeoflorin with a functional group in place of benzoyl group and/or a different functional group in stead of Rl. We suggested that benzoyl group of benzoyloxypaeoniflorin substitued instead of 5-carbon OH group on glycoside moiety paeoniflorin played role of the metabolite in case of a platelet aggregation inhibition activity. Paeoniflorin showed more strong inhibition by thrombin than collagen. Therefore, it may be destructed a calcium metabolite as a forming $Ca^2＋$ chelate. Compound 3a may be that other functional group instead of OH group of 5-carbon on glycoside moiety of paeoniflorin and/or OH group of benzoyl moiety of paeoniflorin played role of the metabolite in a platelet aggregation inhibition.